Comparison on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fibre lasers

C.-Y. Yang, Y.-H. Lin, C.-L. Wu, C.-H. Cheng, Din-ping Tsai, G.-R. Lin

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

© 2018 Astro Ltd.Comparisons on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fiber lasers (EDFLs) are performed. As opposed to the graphite nano-particles obtained by physically triturating the graphite foil, the tri-layer graphene nano-sheets is obtained by electrochemically exfoliating the graphite foil. To precisely control the size dispersion and the layer number of the exfoliated graphene nano-sheet, both the bias of electrochemical exfoliation and the speed of centrifugation are optimized. Under a threshold exfoliation bias of 3 volts and a centrifugation at 1000 rpm, graphene nano-sheets with an average diameter of 100 ± 40 nm can be obtained. The graphene nano-sheets with an area density of 15 #/?m2 are directly imprinted onto the end-face of a single-mode fiber made patchcord connector inside the EDFL cavity. Such electrochemically exfoliated graphene nano-sheets show comparable saturable absorption with standard single-graphene and perform the self-amplitude modulation better than physically triturated graphite nano-particles. The linear transmittance and modulation depth of the inserted graphene nano-sheets are 92.5% and 53%, respectively. Under the operation with a power gain of 21.5 dB, the EDFL can be passively mode-locked to deliver a pulsewidth of 454.5 fs with a spectral linewidth of 5.6 nm. The time-bandwidth product of 0.31 is close to the transform limit. The Kelly sideband frequency spacing of 1.34 THz is used to calculate the chirp coefficient as -0.0015.
Original languageEnglish
Article number065102
JournalLaser Physics
Volume28
Issue number6
DOIs
Publication statusPublished - 1 Jun 2018
Externally publishedYes

Keywords

  • erbium-doped fiber lasers
  • exfoliated graphene nano-sheets
  • mode-locking
  • triturated graphite nano-particles

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Instrumentation
  • Condensed Matter Physics
  • Industrial and Manufacturing Engineering

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